<template>

  <el-container class="home-container">
    <!--头部区域-->
    <el-header>
      <div>
        <img src="../../assets/heima.png" alt="">
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!--页面主题区-->
    <el-container>
      <!--侧边栏-->
      <el-aside :width="isCollapse ? '64px' : '200px'">
        <div class="toggle-button" @click="toggleCollapse"><<>></div>
        <!--左侧边栏菜单区-->
        <el-menu
            background-color="#333744" text-color="#fff" active-text-color="#409EFE"
            unique-opened :collapse="isCollapse" :collapse-transition="false" :router="true"
            :default-active="activePath">
          <!--一级菜单-->
          <el-submenu :index="item.id + ''" v-for="item in menuList" :key="item.id">
            <!--index里面只能是字符串类型，拼接一个空字符串就好啦-->
            <!--一级菜单模板区-->
            <template slot="title">
              <i :class="iconsObj[item.id]"></i>
              <span>{{ item.authName }}</span>
            </template>
            <!--二级菜单-->
            <el-menu-item :index="'/' + towItem.path" v-for="towItem in item.children" :key="towItem.id"
                          @click="saveNavState('/' + towItem.path)">
              <template slot="title">
                <i class="el-icon-menu"></i>
                <span>{{ towItem.authName }}</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      <!--右侧内容主体-->
      <el-main>
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  name: "Home",
  data() {
    return {
      //左侧菜单数据
      menuList: [],
      iconsObj: {
        // 一级菜单的icon图标
        147: 'el-icon-magic-stick',
        125: 'iconfont icon-users',
        103: 'iconfont icon-tijikongjian',
        101: 'iconfont icon-shangpin',
        102: 'iconfont icon-danju',
        145: 'iconfont icon-baobiao'
      },
      //是否折叠左侧菜单栏区
      isCollapse: false,
      //被激活的链接地址
      activePath: ''
    }
  },
  created() {
    this.getMenuList()
    this.activePath = window.sessionStorage.getItem('activePath')
  },
  methods: {
    logout() {
      //清空token值
      window.sessionStorage.clear()
      this.$router.push('/login')   //跳转到登录页
    },
    //获取所有的菜单
    async getMenuList() {
      const {data: res} = await this.$http.get('menus')
      if (res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menuList = res.data
      // console.log(res)
    },
    //点击按钮，切换菜单的折叠与展开
    toggleCollapse() {
      this.isCollapse = !this.isCollapse
    },
    //保存链接的激活状态（二级菜单高亮）
    saveNavState(activePath) {
      window.sessionStorage.setItem('activePath', activePath)
      this.activePath = activePath
    }
  }
}
</script>

<style lang="less" scoped>
.home-container {
  height: 100%; /*或者： height:100vh*/
}

.el-header {
  background-color: #373D41;
  display: flex;
  justify-content: space-between; /*左右贴边对齐*/
  padding-left: 0;
  align-items: center; /*弹性盒退出按钮居中*/
  color: #fff;
  font-size: 20px;

  > div {
    display: flex;
    align-items: center; /*居中对齐弹性盒的各项*/

    span {
      margin-left: 25px;
    }
  }
}

.el-aside {
  background-color: #333744;

  .el-menu {
    border-right: none;
  }
}

.el-main {
  background-color: #eaedf1;
}

.iconfont { /*左侧菜单图标间距*/
  margin-right: 9px;
}

.toggle-button {
  background-color: #4a5064;
  color: #fff;
  font-size: 15px;
  text-align: center;
  line-height: 24px;
  letter-spacing: 0.2em; /*letterSpacing 属性设置字符之间的空白。*/
  cursor: pointer; /*该属性定义了鼠标指针放在一个元素边界范围内时所用的光标形状*/
}
</style>